Effect of brimonidine tartrate ophthalmic solution 0.2% on pupil size in normal eyes under different luminance conditions.

PURPOSE: To evaluate the effect of brimonidine tartrate ophthalmic solution 0.2% (Alphagan) on pupil size in normal eyes. Three luminance conditions were used to assess the potential use of brimonidine in postoperative refractive patients who experience nighttime vision problems related to large pupil size. SETTING: McDonald Eye Associates, Fayetteville, Arkansas, USA. METHODS: Pupil size was measured in 16 eyes of 16 participants with the Colvard pupillometer under 3 luminance conditions. One drop of brimonidine 0.2% was administered to each patient. Pupil size was then measured using the same technique 30 minutes and 4 and 6 hours after drop administration. RESULTS: Under scotopic conditions, 100% of the pupils showed significant miosis at 30 minutes (P <.05). The effect continued in all eyes for 4 hours. At 6 hours, a miotic effect was still present in 81.3%. However, under photopic luminance, there was no significant effect on pupil size in all 16 eyes (P >.05). The pupil size in 5 eyes (31.2%) was not affected at 30 minutes or 4 or 6 hours. At 6 hours, 15 eyes (93.8%) had returned to their preinstillation size. CONCLUSION: Brimonidine tartrate 0.2% had a significant effect in decreasing pupil size under scotopic conditions. The results indicate that the drug can decrease night-vision difficulties such as halos, star bursts, glare, and monocular diplopia in postoperative refractive patients.

Feasibility of bimanual microincision phacoemulsification in hard cataracts.

PURPOSE: The purpose of this work was to assess the feasibility of bimanual phacoemulsification in hard cataracts of N3+ using WhiteStar technology of Soveriegn (Advanced Medical Optics, Santa Ana, CA, USA). SETTING: Ain-Shams University Hospitals, Ophthalmology Department, Cairo, Egypt. DESIGN: A randomized prospective noncomparative study. METHODS: A randomized prospective study of 33 consecutive cases (N3+ or more) was conducted, phacoemulsification using a bimanual microincision technique using the Sovereign with WhiteStar technology phacoemulsification machine. One phaco mode was used in all eyes. The ultrasound power was set at 30-25% according to the hardness of the nuclei, duty cycle of 33%, flow rate of 20-28 cm3/min, and vacuum of 240 mmHg. Occlusion mode was on. Nine eyes received rollable intraocular lenses (IOL) of ThinOptx, whereas 24 eyes had been implanted with hydrophobic acrylic foldable IOL (Sensar OptiEdge SA40e of AMO) through a third incision. Study parameters were effective phacotime (EPT), presence of wound burn, degree of immediate postoperative iritis, amount of infusion solution used, and total operating time. RESULTS: The mean EPT was 4.3 s with an average ultrasound used of 5.7%. The mean operating time was 11 min and 20 s. Although the nuclear hardness was of grade 3 or above (in a scale of 5), there were no cases of thermal burn; P=0.005. Only three eyes suffered postoperative iritis 2+, which resolved within 1 week on topical steroids, statistically nonsignificant, P=0.2. The amount of infusion solution was less than that used in conventional coaxial phaco. This technique induced considerably less corneal astigmatism than surgery using conventional corneal incisions. CONCLUSIONS: Hard cataracts of N3 or more could be safely removed through an incision of 1.4 mm incision using bimanual micro-phaco.